Tesla is closing a dozen solar facilities in 9 states, including some Arizona operations.

Electric car maker Tesla's move last week to cut 9 percent of its workforce will sharply downsize the residential solar business it bought two years ago in a controversial $2.6 billion deal, according to three internal company documents and seven current and former Tesla solar employees.

The latest cuts to the division that was once SolarCity — a sales and installation company founded by two cousins of Tesla CEO Elon Musk — include closing about a dozen installation facilities, according to internal company documents, and ending a retail partnership with Home Depot that the current and former employees said generated about half of its sales.

About 60 installation facilities remain open, according to an internal company list reviewed by Reuters. An internal company email named 14 facilities slated for closure, but the other list included only 13 of those locations.